INTERNATIONAL JOURNAL OF AGRICULTURAL TECHNOLOGYVolume 16, No. 01, Month JANUARY, Year 2020, Pages 119 - 128
Classification and diversity assessment of pyricularia oryzae based on leaf and neck blast pathogenesis on khao dawk mali 105
Pradapphai, P. and Parinthawong, N.
Abstract Download PDFForty isolates of P. oryzae were obtained from disease outbreak areas in various
regions of Thailand. The fungi were divided into two groups; group 1 included 2 isolates which
cause only neck blast with disease score of 7 – 9 and group 2 included 23 isolates which cause
leaf and neck blast symptoms with disease scores of 5 – 6 and 7 – 9, respectively. The two
groups of fungi were tested on 31 NILs. The avirulence genes including Avr-Pik (Avr-Pik, Avr-
Pikm, Avr-Pikp), Avr-Pi1, Avr-Pi3, Avr-Pi5(t), Avr-Pi7(t), Avr-Pi9, Avr-Pi20, Avr-Pii and Avr-
Pita were found in both groups whereas Avr-Pi11, Avr-Pi12, Avr-Pi19, Avr-Pia, Avr-Pib, Avr-
Pikh, Avr-Piks, Avr-Pish, Avr-Pita, Avr-Piz, Avr-Piz-5 and Avr-Piz-t were detected only in the
group 2. The results explained the relationship between fungi and the avirulence genes
functioned at different stages of rice.
leaf blast, neck blast, Pyricularia oryzae, avirulence (Avr) genes